Add support for command-specific env for hooks

src/rebar_core.erl

@@ -234,12 +234,15 @@ execute(Command, Modules, Config, ModuleFile) ->
             %% responds to this command
             erlang:put(operations, erlang:get(operations) + 1),
 
+            %% Check for and get command specific environments
+            Env = setup_envs(Config, Modules),
+
             %% Run the available modules
-            apply_hooks(pre_hooks, Config, Command),
+            apply_hooks(pre_hooks, Config, Command, Env),
             case catch(run_modules(TargetModules, Command,
                                    Config, ModuleFile)) of
                 ok ->
-                    apply_hooks(post_hooks, Config, Command),
+                    apply_hooks(post_hooks, Config, Command, Env),
                     ok;
                 {error, failed} ->
                     ?FAIL;
@@ -304,14 +307,19 @@ run_modules([Module | Rest], Command, Config, File) ->
             {Module, Error}
     end.
 
-apply_hooks(Mode, Config, Command) ->
+apply_hooks(Mode, Config, Command, Env) ->
     Hooks = rebar_config:get_local(Config, Mode, []),
     lists:foreach(fun apply_hook/1,
-                  [Hook || Hook <- Hooks, element(1, Hook) =:= Command]).
+                  [{Env, Hook} || Hook <- Hooks, element(1, Hook) =:= Command]).
 
-apply_hook({Command, Hook}) ->
+apply_hook({Env, {Command, Hook}}) ->
     Msg = lists:flatten(io_lib:format("Command [~p] failed!~n", [Command])),
-    rebar_utils:sh(Hook, [{abort_on_error, Msg}]).
+    rebar_utils:sh(Hook, [{env, Env}, {abort_on_error, Msg}]).
+
+setup_envs(Config, Modules) ->
+    lists:flatten([M:setup_env(Config) ||
+                      M <- Modules,
+                      erlang:function_exported(M, setup_env, 1)]).
 
 acc_modules(Modules, Command, Config, File) ->
     acc_modules(select_modules(Modules, Command, []),

src/rebar_port_compiler.erl

@@ -27,7 +27,8 @@
 -module(rebar_port_compiler).
 
 -export([compile/2,
-         clean/2]).
+         clean/2,
+         setup_env/1]).
 
 -include("rebar.hrl").
 
@@ -94,14 +95,7 @@ compile(Config, AppFile) ->
         [] ->
             ok;
         _ ->
-            %% Extract environment values from the config (if specified) and
-            %% merge with the default for this operating system. This enables
-            %% max flexibility for users.
-            DefaultEnvs  = filter_envs(default_env(), []),
-            PortEnvs = rebar_config:get_list(Config, port_envs, []),
-            OverrideEnvs = filter_envs(PortEnvs, []),
-            RawEnv = DefaultEnvs ++ OverrideEnvs ++ os_env(),
-            Env = expand_vars_loop(merge_each_var(RawEnv, [])),
+            Env = setup_env(Config),
 
             %% One or more files are available for building.
             %% Run the pre-compile hook, if necessary.
@@ -152,8 +146,15 @@ clean(Config, AppFile) ->
     %% Run the cleanup script, if it exists
     run_cleanup_hook(Config).
 
-
-
+setup_env(Config) ->
+    %% Extract environment values from the config (if specified) and
+    %% merge with the default for this operating system. This enables
+    %% max flexibility for users.
+    DefaultEnvs  = filter_envs(default_env(), []),
+    PortEnvs = rebar_config:get_list(Config, port_envs, []),
+    OverrideEnvs = filter_envs(PortEnvs, []),
+    RawEnv = DefaultEnvs ++ OverrideEnvs ++ os_env(),
+    expand_vars_loop(merge_each_var(RawEnv, [])).
 
 %% ===================================================================
 %% Internal functions